Pacemaker lead for cerclage pacing

ABSTRACT

A pacemaker lead for cerclage pacing includes a lead fixing part including a fixing tip whose diameter becomes gradually smaller toward an end of a distal part thereof, a plurality of bipolar electrodes that come into close contact with heart muscle, in an outer circumference of the lead fixing part, and a guide wire insertion through hole through which a guide wire can be inserted thereinto, a lead body part configured to be extended to the lead fixing part, having a stylet insertion through hole formed therein, and a body fixing part formed in a bent shape so as to be fixed to an inner wall of the coronary sinus, and a stylet inserted into the stylet insertion through hole, enabling the pacemaker lead for cerclage pacing to be easily moved within the body of the patient.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims priority to Korean Patent Application No.KR10-2018-0140401, filed 15 Nov. 2018, the entire content of which isincorporated herein for all purposes by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention generally relates to a pacemaker lead for cerclagepacing. More particularly, the present invention relates to a pacemakerlead for cerclage packing, which moves along the coronary sinus andreaches the interventricular septum, enabling efficient electricaltransmission as the pacemaker lead is close to the His bundle, andincludes a stylet, having improved pushability so that the lead can beeasily moved in a patient's body.

Description of the Related Art

An artificial pacemaker was first introduced in 1958 by Furman S. andRobinson G., etc. Since then, the pacemaker has been used as animportant treatment of a bradyarrhythmia patient. Recently, theartificial pacemaker has been used as an important treatment ofarrhythmia diseases such as complete auriculoventricular block or highdegree auriculoventricular block, or sick sinus syndrome accompanyingsymptoms. Treatment by the pacemaker is a treatment method toartificially generate electrical impulses by use of the artificialpacemaker when electric stimulus of the heart does not normally flow.

FIG. 1 shows a cardiac conduction system. Referring to FIG. 1,electrical conduction of the heart is made by passing through anatrioventricular node from a sinoatrial node within an atrium, andthrough Purkinje fibers in a right bundle and a left bundle divided fromthe His bundle in a ventricle.

In an electrocardiogram (“ECG”), the QRS complex is generated by adepolarization process of a ventricular muscle, and a Q wave refers to afirst downward deflection immediately following a P wave, an R waverefers to a first upward deflection, and an S wave refers to a downwarddeflection following the R wave. A width of QRS means a period of timeduring which electricity is being conducted to the entire ventricles ofthe heart from the His bundle. In a normal state, the width of QRS isabout 0.12 seconds (about 90 ms). In this regard, if the width of QRS ismore than 0.12 seconds (120 ms), this suggests intraventricularconduction disturbance. As the electric conduction time is long, the QRSwidth is widened, but if the electric conduction time is short, the QRSwidth is narrowed. The wide QRS causes ventricular desynchronization dueto failure to unify motions of the ventricles, bringing a side effectthat the ventricular function is lost.

That is, if electric stimulus is applied to a point close to the Hisbundle located in the interventricular septum, the electric conductiontime is shortened and a narrow QRS can be obtained. Accordingly, theelectric stimulus can be effectively transmitted.

However, it is difficult to accurately find the His bundle located inthe interventricular septum during an operation. Although the His bundleis found and a pacemaker lead is fixed to the His bundle, the pacingthreshold is high, so a defect that the battery life of the pacemaker isshortened is produced.

In this regard, a number of various methods to find a position to fix apacemaker lead, to replace the His bundle, have been researched. Apaper, JACC Vol. 69, No. 25, Jun. 27, 2017, p. 3099-3114 (Non-patentLiterature 1), arranges various methods associated with positions to fixpacemaker leads developed according to a conventional art. FIG. 2 is apicture attached to the said paper, showing various positions at whichthe pacemaker leads developed according to a conventional art are fixed.

First, in a method to fix the pacemaker lead at a right ventricular apex(“RVA”), a QRS of about 172 ms was measured, showing a wider QRS than aQRS numerical value of the His bundle, exhibiting a result that heartfailure (“HF)” or atrial fibrillation was caused, thereby furtheraggravating a patient's condition.

A method to fix the pacemaker lead at a right ventricular outflow tract(“RVOT”) or a right ventricular septal (“RV septal”) exhibited a QRSvalue of about 165 ms, which is an excellent value, as compared with themethod to fix the pacemaker lead at the RVA. However, like the method tofix the pacemaker lead at the RVA, heart attack, atrial fibrillation,etc. were caused. Also, the operations were successful only for about66% of the patients, and the operations exhibited difficulty.

As an alternative, a method to fix the lead at a left ventricle (“LV”)has been researched. The method to fix the lead at the LV includesfixation of the lead at an external membrane of the LV and fixation ofthe lead at an internal membrane of the LV. When the lead is fixed atthe external membrane of LV rather than at the external membrane of LV,excellent physiological electrical activation (narrow QRS) wasexhibited, indicating that efficient electric transmission is available.However, according to a method to fix the lead at the LV, the pacemakerlead pierces into a thin membrane between the right atrium and the leftatrium to enter into the LV, and thus, this method has a problem ofmaking an operation difficult.

US Patent Application Publication Nos. 2010/0298841 and 2013/0231728address a method for positioning a pacemaker lead forcibly in theinterventricular septum by allowing the lead to directly pierce into theright ventricle toward the left ventricle. This method covers a methodof stimulating the left interventricular septum rather than the rightinterventricular septum, which can realize a narrower QRS (145 ms) thanstimulating the right interventricular septum, having an effect toreplace a cardiac resynchronization therapy (CRT). However, the methoddisclosed by these patent applications requires very high invasion,causing artificial loss of the interventricular septum between the leftventricle and the right ventricle. In this regard, a risk that adjacenttissues are torn during operation is very high, and a risk that anembolism due to air or blood clot, etc. is generated is also very high.Also, available access is limited to middle or an apex of the ventricle,not to the base of the ventricle, as a desirable portion. Accordingly,significant risks and limitations are implied in the above-describedmethod.

Recently, a method to complement the defects of the above-describedpatent applications by fixing the lead has been researched. The methoduses a screw-type lead rather than to perforate a bore from the rightventricle to the left ventricle and fixes the lead by rotating a screwuntil the lead reaches the left interventricular septum from the rightinterventricular septum. However, this method is also highly liable todamage other tissues such as tricuspid tissues, and a defect that it isdifficult to move the lead close to the His bundle still remains.

Therefore, there is a demand for researches for a pacemaker lead thatcan effectively transmit electrical stimulus similar to the His bundleand transmit the electric stimulus in a safe and simple manner.

The foregoing is intended merely to aid in the understanding of thebackground of the present invention, and is not intended to mean thatthe present invention falls within the purview of the related art thatis already known to those skilled in the art.

DOCUMENTS OF RELATED ART Patent Documents

-   (Patent Document 1) US 2010/0298841 A1 published on Nov. 25, 2010;    and-   (Patent Document 2) US 2013/0231728 A1 published on Sep. 5, 2013

Non-Patent Documents

-   (Non-patent Document 1) “The Continued Search for Physiological    Pacing”, Journal of the American College of Cardiology, Vol. 69, No.    25, May 3, 2017).

SUMMARY OF THE INVENTION

Accordingly, the present invention has been made keeping in mind theabove problems occurring in the related art, and an object of thepresent invention is to provide a pacemaker lead fixed at the base ofthe interventricular septum close to the His bundle, to effectivelytransmit electrical stimulus to the heart.

Another object of the present invention is to provide a pacemaker leadwhich can find an optimal electrical conduction position according toeach patient by measuring electrocardiograms (ECGs) at several positionsof the interventricular septum, without replacing the lead.

Still another object of the present invention is to provide a pacemakerlead which can be moved in the body of a patient in a simple manner,without requiring any other device, and whose position as fixed is notchanged according to a motion of the heart.

The present invention is not limited to the above-described objects, andanother objects not mentioned above can be clearly appreciated by aperson having ordinary knowledge in the art to which the presentinvention pertains, from the description of the invention as describedbelow.

In order to achieve the above objects, according to one aspect of thepresent invention, there is provided a pacemaker lead for cerclagepacing, the pacemaker lead including: a lead fixing part including afixing tip whose diameter becomes gradually smaller toward an end of adistal part thereof, a plurality of bipolar electrodes which come intoclose contact with a heart muscle in an outer circumference of thepacemaker lead, and a guide wire insertion through hole through which aguide wire can be inserted thereinto; a lead body part configured to beextended to the lead fixing part, having a stylet insertion through holeformed therein, and a body fixing part in a bent form so as to be fixedto an inner wall of the coronary sinus; and a stylet inserted into thestylet insertion through hole, enabling the pacemaker lead for cerclagepacing to be easily moved within the body of a patient.

In an embodiment, a first end of the guide wire insertion through holemay be provided at the end of the distal part of the fixing tip, and asecond end of the guide wire insertion through hole may be provided at alateral side of the lead body part.

In another embodiment, the first end of the guide wire insertion throughhole may be provided at the end of the distal part of the fixing tip,and the second end of the guide wire insertion through hole may beprovided at a lateral side of the lead fixing part.

In a further embodiment, the first end of the guide wire insertionthrough hole may be provided at the end of the distal part of the fixingtip, and the second end of the guide wire insertion through hole may beprovided at an end of a proximal part of the lead body part.

The lead fixing part may be formed of French size (Fr) 2 to 5.5, so asto easily pierce into the heart muscle and to be then fixed thereto, andthe bipolar electrodes may include at least two bipolar electrodes, andmay be configured such that a distance between the electrodes is 2 mm to10 mm, electric signals of the electrodes can be respectively measured,and electrical transmission thereof is enabled.

Also, an end of a distal part of the stylet insertion through hole maybe configured in a closed manner and positioned on the same verticalline as an end of a proximal part of the guide wire insertion throughhole.

The body fixing part may be ductile so as to be spread in a straightline when the stylet is inserted into the stylet insertion through hole,the body fixing part may be elastic so as to be restored to anoriginally bent shape when the stylet is removed, and the body fixingpart may include a plurality of ductile wires provided on a side wallthereof, thus increasing a fixing force.

Also, the stylet may be configured to become stronger from a distal parttoward a proximal part thereof, and the stylet may have a diameter whichbecomes smaller toward an end of the distal part thereof.

According to the present invention, the pacemaker lead is fixed at thebase of the interventricular septum close to the His bundle, thusefficient electrical transmission is enabled.

According to the present invention, as the pacemaker lead includes aplurality of electrodes, electrical stimulus can be checked at severalpositions, and a position to transmit electrical stimulus can be changedfor each patient, without requiring a re-operation.

According to the present invention, as the stylet is inserted into thelead body part, the pacemaker lead can be easily inserted into and movedin a blood vessel, without requiring any other device when the stylet ismoved in the body of a patient.

According to the present invention, the lead fixing part is thin aboutFr 4, and the lead fixing part includes a fixing tip having a diameterof an end thereof that becomes smaller, serving to easily pierce intothe interventricular septum.

According to the present invention, the pacemaker lead can be insertedand fixed in a stable manner, without damaging any other tissues in theheart.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and other advantages of thepresent invention will be more clearly understood from the followingdetailed description when taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is a view showing a cardiac conduction system;

FIG. 2 is a view showing a position at which a pacemaker lead developedaccording to a conventional research is fixed;

FIG. 3 is a view showing a position at which a lead according to thepresent invention is fixed at the interventricular septum;

FIG. 4A is a perspective sectional view of the lead according to anexemplary embodiment of the present invention;

FIG. 4B is a perspective sectional view showing that a fixing part isdeformed by removing a stylet from the lead according to an exemplaryembodiment of the present invention;

FIG. 4C is a view showing a state where a lead body part according to anexemplary embodiment of the present invention is fixed at a coronarysinus;

FIG. 4D is a sectional view of the lead body part according to anexemplary embodiment of the present invention;

FIG. 5A is a perspective sectional view of a body fixing part accordingto an exemplary embodiment of the present invention;

FIG. 5B is a perspective sectional view of a fixing part according to anexemplary embodiment of the present invention;

FIG. 6 is a perspective sectional view of a guide wire insertion throughhole according to another exemplary embodiment of the present invention;

FIG. 7A is a perspective sectional view of a guide wire insertionthrough hole according to a further other exemplary embodiment of thepresent invention;

FIG. 7B is a sectional view of the lead body part according to anotherexemplary embodiment of the present invention;

FIG. 8 is a flowchart showing an operation method using a lead accordingto an exemplary embodiment of the present invention;

FIG. 9A is a picture showing a pressurized septal venogram when acoronary sinus is blocked by use of a balloon catheter;

FIG. 9B is a view showing balloon catheters;

FIG. 10 is a flowchart showing an operation method using a leadaccording to an exemplary embodiment of the present invention;

FIG. 11 is a schematic diagram showing a passage {circle around (1)}into which a guide wire is inserted in an experiment using a pacemakerlead according to the present invention; and

FIG. 12 is an X-ray picture showing a lead inserted through the passage{circle around (1)} of FIG. 11.

DETAILED DESCRIPTION OF THE INVENTION

Hereinbelow, exemplary embodiments of the present invention will bedescribed in detail with reference to the accompanying drawings.Throughout the drawings, the same reference numerals will refer to thesame or like parts.

FIG. 3 is a view showing a position at which a lead according to thepresent invention is fixed at the interventricular septum.

According to the present invention, a pacemaker lead is inserted intothe body of a patient along the same passage as the passage throughwhich to enter into the body of the patient, in “a tissue protectiondevice for mitral valve membrane cerclage procedure” invented by theinventors of the present invention, which was applied for under KoreanPatent No. 10-1563172.

As described above, the pacemaker lead according to the presentinvention is inserted into a coronary sinus and then moves along thecoronary sinus to reach the interventricular septum. A position at whichan end of the lead is fixed is a basal interventricular septum betweenthe His bundle (HBP) and the left ventricular (LV) septum, as indicatedin a red circle by FIG. 3.

Where the pacemaker lead is fixed at the His bundle (HBP), as a narrowQRS can be obtained, it is possible to reduce the electrical conductiontime, enabling efficient electrical transmission. However, it isdifficult to locate an accurate position of the His bundle positioned inthe interventricular septum during an operation, and a pacing thresholdis high even though the pacemaker lead is fixed at the His bundle. Inthis regard, there is a problem in reducing a battery life of thepacemaker lead.

Where the pacemaker lead is fixed at the left ventricular (LV) septum, anarrower QRS than to stimulate the right ventricular (RV) septum can berealized, having an effect to replace the cardiac resynchronizationtherapy (CRT). However, this is a very invasive treatment because thistreatment requires to perforate a bore from the right ventricle to theleft ventricle, so as to insert the lead into the right ventricle andthe left ventricle. In this regard, this method is highly liable todamage other tissues such as the tricuspid valve, etc.

According to the present invention, a portion at the lead is fixed(indicated by a red circle in FIG. 3) is close to the His bundle ratherthan to the left ventricular (LV) septum, having an excellent efficiencyof electrical conduction, the lead may be fixed without perforating theinterventricular septum from the right ventricle to the left ventricle,like the lead located at the left ventricular (LV) septum, and the leadmay be fixed, without damaging other tissues such as the tricuspidvalve.

Also, it is difficult to find a position at the His bundle during anoperation. However, the lead according to the present invention entersalong the coronary sinus tube to be fixed, a position to fix an end ofthe lead can be more easily found.

As described above, the pacemaker lead for cerclage pacing according tothe present invention complements defects of a device to fix an end ofthe lead developed according to a conventional art at the His bundle,and a device to fix the end of the lead at the left ventricle (LV)septum, and maintains all the advantages of these conventional devices.

FIG. 4A is a perspective sectional view of the lead according to anexemplary embodiment of the present invention.

Referring to FIG. 4A, the lead 100 according to an exemplary embodimentof the present invention includes a lead fixing part 110 and a lead bodypart 120.

The lead 100 is formed with a single catheter or a cylindrical tube, andthe materials thereof may include rubber materials, synthetic materials,or a mixture of polyurethane and silicone, which are soft and ductile.

The lead fixing part 110 constitutes a portion to pierce into the heartmuscle to be then fixed and to transmit electrical stimulus. A guidewire insertion through hole 116 through which a guide wire 200 can beinserted is famed inside the leading fixing part 110.

The lead fixing part 110 includes a fixing tip 112 whose diameter isgradually tapered toward to an end of a distal part thereof, and aplurality of electrodes 114 coupled to an outer circumference of thelead fixing part 110, to come into close contact with the heart muscle.

The fixing tip 112 is configured to easily pierce into the heart musclefor each insertion. According to an exemplary embodiment of the presentinvention, the fixing tip 112 is formed to have a diameter thatgradually becomes smaller (that is, in a tapered form) toward an end ofthe distal part thereof.

Also, the lead fixing part 110 has a size of 2 to 5.5 French sizes (Fr),which is configured to be thin so as to easily pierce into the heartmuscle. The size of 4 Fr is preferable, but the lead fixing part 110 mayalso be configured to have a size of 5.1 Fr, 5.2 Fr, etc.

The electrode 114 is a bipolar electrode, coupled to an outercircumference of the lead fixing part 110, and the electrode 114 isprovided in plural. A plurality of the electrodes 114 are coupled to therespective one ends of a plurality of electrode wires 118, and therespective other ends of the plurality of electrode wires 118 areconnected to the pacemaker. Measurement of respective electrical signalsby the electrodes 114 in plural is enabled, and transmission ofelectrical stimulus is also enabled.

For example, if the lead fixing part 110 includes five electrodes, thesignals of the five electrodes are respectively measured, on the basisof which an optimal position is found based on each patient. Then,stimulus of a positive electrode and a negative electrode, or stimulusof a negative electrode and a positive electrode may be provided to afirst electrode and a third electrode respectively, or stimulus of apositive electrode and a negative electrode, or stimulus of a negativeelectrode and a positive electrode may be provided to a fourth electrodeand a fifth electrode respectively.

The lead 100 according to the present invention is capable of selectingelectrodes in a position suitable for each patient for electricaltransmission, as exemplified above.

A plurality of the electrode wires 118 can be inserted in a straightline onto a lateral wall of the lead body part 120. It is also possibleto insert the plurality of electrode wires 118 in a helical form ontothe lateral wall of the lead body part 120.

The plurality of electrodes 114 are mounted at intervals of 2 mm to 10mm. More preferably, the electrodes 114 are mounted at intervals of 2 mmto 3 mm.

As the lead 100 according to the present invention includes a pluralityof bipolar electrodes 114, an optimal position to transmit electricalsignals, which differs from each patient, is detected and theelectricity is transmitted to an electrode close to the detectedposition, thereby enabling more efficient transmission of electricalstimulus. Accordingly, it is possible to adjust a position for theelectrical transmission depending upon a patient, without a re-operationto change a position of the lead.

One end of the guide wire insertion through hole 116 is formed at an endof the distal part of the fixing tip 112, and the other end of the guidewire insertion through hole 116 is formed on a lateral side of the leadbody part 120. The guide wire 200 is inserted into an end of the guidewire insertion through hole 115 formed at the fixing tip 120 and passesthrough the other end of the guide wire insertion through hole 116formed at the lateral side of the lead body part 120.

According to this, the guide wire 200 can be inserted and removed morequickly than a method that the guide wire passes through the entire leadbody part 120.

Wires of synthetic resins such as nylon or metal materials (stainlesssteel, a metal coated with nylon), etc. may be used for the guide wire200. A wire formed by twisting plural thin wires may also be used.Preferably, the guide wire having a diameter of 0.014 inches is used.

Also, the guide wire 200 provides a passage along which the lead 10moves in the body of a patient, and pushability is enhanced when theguide wire 200 is inserted into the lead fixing part 110 and the leadfixing part 110 moves in the body of the patient.

The lead body part 120 is configured to be extended from an end of aproximal part of the lead fixing part 110, having a diameter larger thanthe lead fixing part 110. As the lead body part 120 is located withinthe coronary sinus having a blood vessel that has a relatively largeinner diameter, it is possible that the lead body part 120 has a largerdiameter than the lead fixing part 110. The lead body part 120 includesa body fixing part 122 and a stylet insertion through hole 124.

The stylet insertion through hole 124 into which a stylet 300 isinserted is formed inside the lead body part 120, and the styletinsertion through hole 124 does not communicate with the guide wireinsertion through hole 115 because the end of the distal part thereof isclosed.

The end of the distal part of the stylet insertion through hole 124 islocated on the same vertical line as the end of the proximal part of theguide wire insertion through hole 116.

It is possible that the end of the distal part of the stylet insertionthrough hole 124 may be formed at the distal part of the guide wireinsertion through hole 115 rather than on the vertical line of the endof the distal part of the guide wire insertion through hole 116, therebyallowing the stylet insertion through hole 124 to be formed partially inparallel with the guide wire insertion through hole 120 within the leadbody part 120.

Accordingly, when after the stylet 300 is inserted into the styletinsertion through hole 120, they are pushed by an operator to move thelead 100 in the body of the patient without being bent.

The stylet 300 which is to provide additional solidity for adjustment ofdirection when a catheter, a lead, etc. is moved to desired positions inthe body of the patient. The stylet 300 may be constructed with the samematerial as the guide wire 200, and has the same thickness as or widerthickness than the guide wire 200.

The stylet 300 is formed to be more solid toward the proximal part fromthe distal part thereof. A material of the distal part is ductile so asto be more movable than that of the proximal part, so that the stylet300 can be easily moved along the curved blood vessel in the body of thepatient, and a material of the proximal part is solid so as to receivethe force pushed by the operator.

Accordingly, as the lead 100 formed of a ductile material cannot easilymove to a position desired by the operator when the lead 100 moves inthe body of the patient or in the blood vessel, the lead 100 requiresanother device to help movement thereof. However, the lead 100 accordingto the present invention requires no other device as the stylet 300 isinserted into the stylet insertion through hole 124, enhancingpushability of the lead 100, and the lead 100 can be easily insertedinto the coronary sinus tube to move toward the interventricular septum.

FIG. 4B is a perspective sectional view showing that a body fixing partis deformed by removing a stylet from the lead according to an exemplaryembodiment of the present invention.

In the lead body part 120, a body fixing part 122 is formed at a portionlocated in the coronary sinus, and the body fixing part 122 is formedafter bending one side of the lead body part 120 in a spiral or waveform, etc. and heating the bent side. FIG. 4B shows the body fixing part122 in a wave form, but the body fixing part 122 may be modified invarious forms to press the inner wall of the coronary sinus.

As the body fixing part 122 is formed by heating one side of the softlead body part 120, the body fixing part 122 is elastic so as to bespread and restored to the portion bent in a spiral or wave formaccording to the movement of the heart, thereby being capable ofabsorbing impact applied to the lead fixing part 110.

The body fixing part 122 is ductile so as to be spread in a straightline when the stylet 300 is inserted into the stylet insertion throughhole 124 and also elastic so as to be restored to an originally bentshape when the stylet 300 is removed.

Accordingly, after the lead 100 is prepared in a straight line outsidethe body of the patient by inserting the stylet 300 into the lead bodypart 120 at which the body fixing part 122 is formed, the lead 100enters into the body of the patient. If the stylet 300 is removedoutside the body of a patient after the lead fixing part 110 is fixed atthe interventricular septum, the body fixing part 122 is restored to theoriginally bent shape to be then fixed at the coronary sinus.

FIG. 4C is a view showing a state that a lead body part according to anexemplary embodiment of the present invention is fixed at a coronarysinus. As shown therein, the body fixing part 122 comes into contactwith two or three points on the inner wall of the coronary sinus,thereby slightly pressing the coronary sinus. The degree that the leadbody part 120 presses the coronary sinus is so slight as not to damagethe coronary sinus. The coronary sinus is pressed with a force to such adegree that the lead body part 120 can be fixed stably in the body ofthe patient. Due to this, the lead 100 is stably fixed without beingdeviated from the originally fixed position despite movement of theheart.

FIG. 4D is a sectional view of the lead body part according to anexemplary embodiment of the present invention.

As shown in FIG. 4D, the stylet insertion through hole 124 is formedinside the lead body part 120. The stylet 300 is inserted into thestylet insertion through hole 124, and the electrode wires 118 areinserted onto the lateral side of the lead body part 120.

FIG. 5A is a perspective sectional view of a body fixing part accordingto an exemplary embodiment of the present invention, and FIG. 5B is aperspective sectional view of a body fixing part according to anexemplary embodiment of the present invention.

Referring to FIGS. 5A and 5B, another body fixing part 122 according toan exemplary embodiment of the present invention includes a reinforcingmeans 123. The reinforcing means 123 is formed of a single ductile wireor a plurality of ductile wires.

The reinforcing means 123 is to reinforce the fixing power when the bodyfixing part 122 is locked to the coronary sinus, being directed tominimize movement of the lead 100 according to the heart beat when thebody fixing part 122 is bent to thereby come into contact with thecoronary sinus to fix the lead 100.

As the reinforcing means 123 is a ductile wire, the body fixing part 122is spread to be in a straight line if the stylet 300 is inserted intothe stylet insertion through hole 124, and is deformed to be bent backif the stylet 300 is removed.

FIG. 6 is a perspective sectional view of a guide wire insertion throughhole according to another exemplary embodiment of the present invention.

Referring to FIG. 6, the guide wire insertion through hole 116 accordingto another exemplary embodiment of the present invention has one endformed at an end of the distal part of the fixing tip 112 and the otherend formed at a lateral side of the lead fixing part 110.

The other end of the guide wire insertion through hole 116 is formed atthe distal part rather than at a point to which the electrode 114 iscoupled, and the stylet insertion through hole 124 is elongated up tothe inside of the lead fixing part 110. Preferably, one end of thestylet insertion through hole 124 is formed at the same straight line asthe other end of the guide wire insertion through hole 116. Accordingly,the stylet 300 is inserted into the stylet insertion through hole 123formed up to the lead fixing part 110, thereby enhancing pushability ofthe lead 100. Also, the guide wire 200 may be inserted and removed morequickly than a configuration wherein the guide wire 200 passes throughthe entire lead body part 120.

At this time, the stylet 300 has a diameter tapered toward the distalpart of the stylet 300 so as to be inserted into the lead fixing part110.

FIG. 7A is a perspective sectional view of a guide wire insertionthrough hole according to a further other exemplary embodiment of thepresent invention.

One end of the guide wire insertion through hole 116 is formed at an endof the distal part of the fixing tip 112 and the other end thereof isformed at an end of the proximal part of the lead body part 120.

According to a guide wire insertion through hole of a further otherexemplary embodiment of the present invention, if the guide wire 200 isinserted into the guide wire insertion through hole 116, one side of theguide wire 200 passes out of the end of the proximal part of the leadbody part 120.

FIG. 7B is a sectional view of the lead body part according to anotherexemplary embodiment of the present invention. In other words, FIG. 7Bshows a section of the lead body part 120. According to the lead bodypart 120 according to a further other exemplary embodiment of thepresent invention, the stylet insertion through hole 124 and the guidewire insertion through hole 116 are formed in parallel with each otherinside the lead body part 120. The electrode wire 118 is coupled to thelead body part 120 along the lateral wall of the lead body part 120.

FIG. 8 is a flowchart showing an operation method using a lead accordingto an exemplary embodiment of the present invention.

Referring to FIG. 8, in a method of performing an operation using apacemaker lead for cerclage packing according to the present invention,a balloon tipped guiding catheter 400 is first inserted into the body ofa patient, to check a septal vein. The balloon tipped guiding catheter400 is a catheter formed with a balloon at an upper part thereof, asshown in FIG. 9B. After the catheter 400 is inserted through superiorvein cava and the coronary sinus, external air is injected into thecatheter 400 to inflate the balloon, thereby blocking the coronarysinus. According to this, the blood flow in the coronary sinus isblocked, causing pressure of the coronary sinus to be increased, therebyinflating the coronary sinus. Thereafter, a septal vein located at theinterventricular septum is found from a pressurized venogram (refer toFIG. 9A).

In lieu of the balloon tipped guiding catheter 400, a catheter havingone side to which a tip is coupled (not shown) is also available. Thetip has a diameter similar to an inner diameter of the blood vessel andblocks the coronary sinus, being capable of increasing the pressure ofthe coronary sinus.

Then, the guide wire 200 is inserted into the superior vein cava, thecoronary sinus, and the found septal vein. At this time, if a septalvein is not found, or the septal vein is not located at a positiondesired by the operator, the heart muscle can be perforated by insertinga perforating device thereinto. The perforating device is optional andis not necessarily required.

The lead 100 according to the present invention is inserted along theinserted guide wire 200.

FIG. 10 is a flowchart showing an operation method using a leadaccording to an exemplary embodiment of the present invention. Referringto FIG. 10, an operation will be explained below.

First, a lead 100 according to the present invention, prepared outsidethe body of a patient before a stylet 300 is inserted into the lead 100,is shown. The lead 100 is prepared to have a body fixing part 122 bentin a spiral or wave bent form, etc. Then, the lead 100 is prepared byinserting the stylet 300 into the lead outside the body of the patient,so that the body fixing part 122 is in a state of being spread. The lead100 as prepared above is inserted into the body of the patient along theguide wire 200 inserted into the body of the patient earlier.

Next, it is shown that the lead 100 prepared in a straight line isinserted into the body of the patient and moves along the coronarysinus. The lead 100 according to the present invention includes thestylet 300, thereby enhancing pushability of the lead 100.

Last, the lead 100 moves along the guide wire 200 to cause the leadfixing part 110 to be fixed at the interventricular septum. If thestylet 300 is removed, the body fixing part 122 is recovered to theoriginally bent form in a wave or spiral form, etc. as shown therein andthen fixed at the coronary sinus as bent.

According to this, there is an advantage that the lead 100 is notchanged at the position once fixed. Also, as the lead 100 includes aplurality of electrodes 114, it is possible to find a position forelectrical transmission suitable for each patient, without performing are-operation to move the position of the lead 100, and efficientlytransmit the electricity.

FIG. 11 is a schematic diagram showing a passage {circle around (1)}into which a guide wire is inserted in an experiment using a pacemakerlead according to the present invention. A passage to insert the guidewire along the coronary sinus into the septal vein to pass through theinterventricular septum is shown.

In this experiment, the lead according to the present invention isinserted along the passage through which the guide wire 200 is inserted.

FIG. 12 is an X-ray picture showing a lead inserted through the passage{circle around (1)} of FIG. 11 and then fixed at the base of theinterventricular septum.

Referring to FIG. 12, four bipolar electrodes are coupled to thepacemaker lead according to the present invention, wherein an intervalbetween the electrodes is set 2 mm. The pacemaker lead is inserted intothe superior vein cava, the coronary sinus, and the septal vein alongthe guide wire inserted through the passage {circle around (1)} shown inFIG. 11 and fixed at the basal interventricular septum.

Electrical transmission efficiency when the lead according to anexemplary embodiment of the present invention is fixed at the basalinterventricular septum will be compared with electrical transmissionefficiency when a lead is fixed at a position to fix the lead accordingto a conventional research.

As described above in the Description of the Related Art section, thepositions at which the lead is fixed according to a conventionalresearch include an RV apical pacing, an RV septal pacing, an LVepicardial pacing, an LV endocardial pacing, an LV apical pacing and anLV near apical pacing.

As seen in the picture of FIG. 12, among the four electrodes of the leadinserted into the body of the patient through the guide wire inserted inthe direction of passage {circle around (1)} and fixed at the intraseptal pacing, two electrodes are selected (second and third electrodes,second and fourth electrodes, first and third electrodes or first andfourth electrodes), to which electricity is transmitted, measuring QRSvalues, and after inserting the lead according to the conventionalmethod, electricity is transmitted and QRS values are measured. Table 1below indicates QRS values in the experiment.

TABLE 1 Location QRS (Unit: msec) Self rhythm 83 RV septal pacing 93 RVapical pacing 165 Intra septal pacing(second and third electrodes) 75Intra septal pacing(first and third electrodes) 75 Intra septalpacing(second and fourth electrodes) 75 Intra septal pacing(first andfourth electrodes) 75

Referring to Table 1, when the lead was fixed at the basalinterventricular septum in the direction of passage {circle around (1)},all narrow QRS values were able to be obtained. To compare with thevalues of the comparative examples (the first to three locations inTable 1), excellent results are indicated. Where the electrodes arelocated in the interventricular septum, narrow QRS values having norelatively great difference are exhibited, without regard to which twoelectrodes are selected among the four electrodes. This indicates moreexcellent values than QRS where the lead is inserted according to theconventional method. However, if an electrode moves near to an internalmembrane of the right ventricle or the external membrane of the leftventricle, a phenomenon that the QRS becomes long again is shown. Thisfact is interpreted to mean that an ideal position to fix the electrodeis in the interventricular septum.

Accordingly, using the lead according to the present invention, the leadis fixed at the basal interventricular septum close to the His bundle,enabling efficient electrical transmission. As the lead according to thepresent invention includes a plurality of electrodes, electricalstimulus at several positions can be checked. Also, as the leadaccording to the present invention does not damage other tissues in theheart, the pacemaker lead can be inserted and fixed in a stable manner.

Although preferred embodiments of the present invention have beendescribed for illustrative purposes, those skilled in the art willappreciate that various modifications, additions and substitutions arepossible, without departing from the scope and spirit of the inventionas disclosed in the accompanying claims. Accordingly, the exemplaryembodiments as described above are for illustrative purposes and shouldnot be construed without limitation thereto.

What is claimed is:
 1. A method of performing intra-septal pacing in apatient's heart, comprising: having a pacemaker lead comprising: (a) alead body comprising a body fixing part that has a straightconfiguration, but self-bends into a spiral or wave form; (b) a leadfixing part having a plurality of electrodes thereon; (c) a channel fora stylet, inserting a stylet into the channel to make the body fixingpart have a straight configuration; inserting the pacemaker lead intothe patient's body; advancing the pacemaker lead into a coronary sinusof the patient's heart; advancing the pacemaker lead to aninterventricular septum of the patient's heart; fixing the lead fixingpart into the interventricular septum; positioning the body fixing partinside the coronary sinus; withdrawing the stylet from the pacemakerlead, thereby causing the body fixing part to self-bend into a spiral orwave form within the coronary sinus; activating the electrodes toprovide intra-septal pacing in the patient's heart.
 2. The method ofclaim 1, wherein the body fixing part in spiral or wave form pressesagainst the coronary sinus.
 3. The method of claim 2, wherein the bodyfixing part comes into contact with two or three points at an inner wallof the coronary sinus.
 4. The method of claim 3, wherein the stylet isstiffer at a proximal part than at a distal part.
 5. The method of claim2, wherein the stylet is stiffer at a proximal part than at a distalpart.
 6. The method of claim 1, wherein the position of the lead fixingpart is between a His bundle and left ventricular septum of thepatient's heart.
 7. The method of claim 6, wherein the stylet is stifferat a proximal part than at a distal part.
 8. The method of claim 1,wherein the body fixing part has a spiral or wave form prior toinsertion of the stylet into the channel.
 9. The method of claim 8,wherein the stylet is stiffer at a proximal part than at a distal part.10. The method of claim 1, wherein the stylet is stiffer at a proximalpart than at a distal part.